Research Abstracts Online
January 2010 - March 2011

PI: Fernando Porté-Agel, Fellow

Large-Eddy Simulation of the Atmospheric Boundary Layer

Researchers use LES to study the turbulent transport of heat, momentum, water vapor, and pollutants in the atmospheric boundary layer. LES is the state-of-the-art numerical technique to calculate the unsteady three-dimensional transport in turbulent flows. Until now, LES has not been sufficiently faithful to the physics of the atmospheric boundary layer, the main weakness being associated with the limited ability to account for the dynamics that are not explicitly resolved in the simulations. The main goal of this research is to address those limitations in order to make LES a more reliable tool to study land-atmosphere exchange processes.

In particular, the objectives are: to develop and implement better subgrid-scale models to accurately account for the effect of the non-resolved scales (smaller than grid size) on the dynamics of the resolved turbulent fields; to develop improved boundary conditions for the simulations, based on results from wind tunnel experiments as well as numerical experiments; to develop parameterizations for the interactions between turbulence and chemical transformations in turbulent boundary layer flows; to develop a computational fluid dynamics framework (based on the group’s LES code) for optimal design of wind energy projects, in particular, to study the interaction between atmospheric turbulence and wind turbine and wind energy parks; and to implement and use massive parallelization of the group's LES code in order to obtain unprecedented high resolutions of the flow over complex terrain for several applications (including wind energy applications).